Response of guinea pigs to the synthetic peptide-M of the uveitogenic, retinal S-antigen: antisera immunofluorescent reactivity on normal guinea pig retina.

S-antigen can elicit an experimental autoimmune uveitis (EAU) and pinealitis (EAP) in experimental animals. The sera of these animals have immunohistochemical reactivity with the photoreceptor cells of normal retina and pinealocytes. Lewis rats injected with the synthetic peptide-M corresponding to a specific sequence of S-antigen also develop an EAU and EAP. In this study we have investigated the immunohistochemical reactivity pattern of sera of guinea pigs injected with peptide-M. We found reactivity in the area of Muller's cells of normal guinea pig retina. Some of the sera showed weak reactivity with retina photoreceptors cells and pinealocytes. These patterns of reactivity are not seen in control sera of uninjected or saline in adjuvant injected guinea pigs. These results are consistent with observations of experimental and human uveitides.